1. Field of the Invention
This invention relates to a sense of physical well-being in an individual and more particularly to the avoidance or reduction of motion sickness which many individuals experience when travelling on the water or in the air, as well as in space.
The invention is further related to the provision of an artificial sensory environment, through acoustic means, which may enable individuals to avoid or reduce the effects of motion sickness.
2. Description of the Related Art
It is generally recognized that motion sickness is greater in sailors working below deck than those above who have the horizon as a visual reference. This has led to the suggestion of the creation of an artificial visual horizon on board ship. See "Performance and Well-Being Under Tilting Conditions: The Effects of Visual Reference and Artificial Horizon" by A. Rolnick, Ph.D. and W. Bles, Ph.D., in "Aviation, Space and Environmental Medicine", Aug. 1989, pages 779-785.
The attenuation of noise by sophisticated muff-type headsets in order to protect the hearing of a pilot is well recognized as for example in "The Art of Noise" in AOPA PILOT, pages 65-69, Dec. 1989. See also, "Fighting Noise With Antinoise", TIME, Dec. 4, 1989, page 94.
The Kuehn U.S. Pat. No. 4,283,798 discloses a diver's helmet which has a series of mercury switches that are responsive to the tilting of the diver's head about the various axes and which operate light emitting diodes that are spaced around the periphery of the face plate in order to indicate visually the true horizon.
The Clancy U.S. Pat. No. 2,288,683 discloses an automobile which has sensing means that are responsive to inclination of the vehicle and other movements and which operate a sound medium within the vehicle.
The Trumble U.S. Pat. No. 3,461,423 discloses a tone generator which is responsive to acceleration or impact of the vehicle
The McGregor et al. U.S. Pat. No. 4,052,720 discloses the use of speakers in a room which are responsive to various environmental sound detectors and which adjust and shape the output from the speakers in response to such factors as background noise level
The Warnaka et al. U.S. Pat. No. 4,562,589 discloses the use of a noise sensor within an airplane which is adapted to produce noise out of phase with the source noise in order to cancel out some of the source noise.
The Fedor U.S. Pat. No. 1,907,402, Leffler U.S. Pat. No. 2,745,091, Boyd et al. U.S. Pat. No. 3,548,400, and Gibson et al. U.S. Pat. No. 4,284,987 disclose means for sensing the inclination or tilt of a vehicle or the like and operating a signal in response thereto.
The article published by Dr. Gillingham in USAFSAM/VN/AV240-3521 discloses an Acoustic Orientation Instrument which has been installed in a T-40 flight simulator as an approach to situational awareness. According to the article the instrument represents air speed as sound frequency, vertical velocity as amplitude modulation rate, angle of attack as an overlaid stutter signal, and bank as the amount of right or left lateralization of the sound signal.